What Sign PDF does
PDFGrover's Sign PDF tool adds your signature to any page of a PDF and gives you back the signed document. For files up to 50 MB and 500 pages, the entire signing process runs in your browser — the file is never uploaded. Larger files fall back to our secure server and are deleted as soon as your download is ready. No account, no watermark, no daily limit either way.
Input limits
- Single file per signing session
- Up to 100 MB per PDF
Three ways to create a signature
- Draw — sign directly in the browser with a mouse, trackpad, or touchscreen. Good for quick signatures on tablets and phones.
- Type — type your name and the tool renders it in a handwriting font. Fastest if you're on a keyboard and don't need your actual hand-written signature.
- Upload — upload a PNG of an existing hand-written signature (ideally with a transparent background). The tool uses the image as the signature stamp.
Placing and adjusting
Once a signature is created, click anywhere on a page to drop it. Drag the stamp to reposition, and use the corner handles to resize. The left-hand thumbnail rail shows which pages already have signatures.
If you need the same signature on every page (common for multi-page contracts), place it once and click Apply to all pages — the exact same stamp, at the same position and size, lands on every page in the document. You can still tweak individual pages after.
File size — why signed PDFs stay lean
A naive sign-then-save can inflate a 5 MB PDF to 150 MB+ if the tool re-rasterises every page as a large JPEG. We avoided that design. Our pipeline:
- Keeps the original PDF's page objects untouched — text stays as vectors, fonts stay as fonts, embedded images stay at their source resolution.
- Embeds each signature stamp as a PNG overlay drawn on top of the original page.
In practice, signing a 5 MB contract produces an output of roughly 5–6 MB, not tens of megabytes.
What this tool is and isn't
- It is a visual signature tool — it places a picture of your signature on the PDF.
- It isn't a cryptographic e-signing service. It does not embed a PKCS#7 / PAdES digital signature, does not record the signer's IP address or identity, and does not produce an audit-trail PDF.
For low-stakes paperwork (proposals, invoices, permission slips, internal documents) a visual signature is what most people mean when they say "sign a PDF". If your legal or compliance team specifically requires a certificate-backed digital signature, use a dedicated e-signature platform — those workflows are outside this tool's scope.
Privacy and file handling
Sign PDF is a pure in-browser tool. Your PDF, the signature images you create, and the signed output all live only in your browser's memory. No file is uploaded, no copy is stored on our server, and no analytics of the document's contents is collected.